An optical information detecting apparatus is formed as an integrated, solid state monolithic structure. The monolithic structure includes a plurality of light sensors disposed on a substrate and electrically isolated from one another, a plurality of light emitting elements disposed on the substrate and electrically isolated from one another, the light sensors being optically isolated from the light emitting elements, and a circuit connected to the light emitting elements to generate light towards a target and connected to the light sensors to detect reflected light from the target, wherein a signal is generated in response to the detected light. The signal is indicative of an optical characteristic of the target.